1.Time course study of growth hormone releasing peptide-6-induced c-fos expression in neurons of feeding-related nuclei of hypothalamus.
Yan-Juan YU ; Jing DONG ; Zheng-Yao JIANG ; Inge DEPOORTERE
Acta Physiologica Sinica 2016;68(1):19-26
The present study was aimed to explore the effects of intraperitoneal injection of growth hormone releasing peptide-6 (GHRP-6), a ghrelin receptor agonist, on food intake and neuronal activity of feeding-related nuclei in the hypothalamus of NMRI mice. Accumulated amount of food intake was measured, and total number of c-fos immunoreactive neurons in arcuate nucleus (ARC), paraventricular nucleus (PVN) and supraoptic nucleus (SON) was counted by immunohistochemistry at 1, 3 and 6 h after the GHRP-6 injection. The results showed that GHRP-6 significantly increased the amount of food intake with a peak at 3 h after the GHRP-6 injection. Meanwhile, GHRP-6 could promote c-fos expression in the ARC and PVN independent of food intake, and the total number of c-fos immunoreactive neurons was peaked at 1 h after injection and then decreased gradually. These results suggest that GHRP-6 may increase food intake in time-dependent manner, which is associated with up-regulations of c-fos protein expression in the ARC and PVN.
Animals
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Arcuate Nucleus of Hypothalamus
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Eating
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Immunohistochemistry
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Male
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Mice
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Neurons
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Oligopeptides
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Paraventricular Hypothalamic Nucleus
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Proto-Oncogene Proteins c-fos
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Receptors, Ghrelin
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Supraoptic Nucleus